Vibratory Polishing of Stainless Steel Components

(2000)

Q. Dear Sir, We are engaged in manufacturing of stainless steel hinges. Recently we have installed vibratory polishing machine for polishing our hinges. The reason for this was that the buffing method was proving too messy, costly and labour consuming. But even the vibratory method is not proving easy either. The finish is dull and the hinges have to be anyway polished first by buffing to remove the film of carbon and other compounds from the stainless sheet. Did we commit a mistake by installing the vibratory machine? Any solutions? Help urgently required.

Sundeep Khandelwal- India

(2000)

A. Sundeep There are a couple of things that you can look at to improve your finished product; however, not knowing what your process is, I can only make some guesses.

1.If you are only using one media and it is ceramic, make sure it is a fine cut with a good burnishing compound. Otherwise, you may need more than a one step process to get finer finish before you use a media without abrasives (porcelain).

2. If you are using steel or S.S. check your compound and make sure you are not retaining affluent.

3. Actually I prefer using a dry organic polishing mix, blended 5 parts porcelain to 1 part treated organic mix; however, it takes some getting use to and unless you have a cover on your machine, it can become a problem. More normal methods use the steel or porcelain in a wet process if there is no deburring required. It also sounds as if you may need some kind of stronger chemical in your process if your parts are dark to start out. Some machines can't run steel very well because of the weight factor; therefore, you have a couple of things to check out.

Tony

AF KentonNova Finishing Systems Inc.
Hatboro, Pennsylvania

(2000)

A. Mr.Khandelwal,

The most efficient and the cheapest method for brightening stainless steel hinges is vibratory (wet) burnishing with stainless steel balls. The (rectangular bowl) burnishing machine (which is rather expensive) must provide 3000 vibrations per minute and have, preferably, an automatic discharge system. In such a machine,the parts are brightened in 10-20 minutes, using an appropriate liquid compound. An important condition is that parts must be perfectly degreased (in an alkaline cleaner) and pickled (in a hydrochloric or sulfuric acid solution and rinsed) before introduction into the machine. The burnishing may also be done in rotating barrels made in stainless steel or steel with interior rubber or polyurethane lining and containing stainless steel balls (2/3 of the volume), water the brightening compound and the parts. But the brightening time will be much longer (12 hours or more).

Emmanuel Popesco- France

(2000)

Q. We are manufacturers of press components made of spring steel. At present we are using Vibrator for processing but we are getting a matte finish instead of required mirror finish.

Jayesh Shah- India

(2002)

A. MR KHANDELWAL,

I SUGGEST A STRONG DEGREASER IN VIBRATORY MACHINE TO REMOVE THE OIL OR BLACKNESS AND THEN BURNISHING USING STEEL MEDIA FOR 60 MINUTES. YOU WOULD REQUIRE A SPECIAL MACHINE FOR BURNISHING AND STRONG ACIDIC COMPOUND FOR BURNISHING.

PRASAD GOGATE- Mumbai, India

September 22, 2009

Q. Hi all. I manufacture anchor winches in Australia, all out of 316 stainless steel. I have purchased a vibrating tumbler machine. My question is if anyone knows what type of compound and ceramic stones I should be placing with stainless steel to get a mirror finish.

Nick Papazoglou manufacturer - Australia

August 25, 2011 -- this entry appended to this thread by editor in lieu of spawning a duplicative thread

I AM A CERAMIC MEDIA MANUFACTURER. WE HAVE ALSO STARTED MANUFACTURING VIBRO & CENTRIFUGAL MACHINES. SIR, I WANT TO UNDERSTAND MORE ABOUT METAL FINISHING AS I ALWAYS GET QUESTIONED BY THE DIFFERENT COMBINATIONS TO USE FOR A PARTICULAR METAL.

ASHISH GOKHALEMANUFACTURER - VADODARA, GUJARAT, INDIA

July 29, 2012

Q. I am a manufacturer of stainless steel hardware items. In order to get mirror finish should I install a vibrator or any other machine to get item well finished?

karan arora- aligarh,India

Hi Nick And Karan. Are you quite sure that your thinking is correct?

It is possible to put a very very fine polishing media into a vibratory finisher for mirror finishing, but it's also possible to dig the foundation for a skyscraper with a teaspoon. The problem in both cases is that it can take nearly forever to reach your goal if you only use a very tiny tool. You could probably start with an almost mirror finished part and mirror finish it, but the abrasive that is required for mirror polishing is so fine that if you start with a rough part it could take forever to get to a mirror finish in one step.

Regards,

Ted Mooney, P.E. RETfinishing.comPine Beach, New Jersey

October 14, 2012

Q. I am having a hard time finding information on polishing stainless steel in a tumbler. Since so many people use stainless steel shot as the medium for polishing other things it is very difficult to search for products and advice.

I have many hardware bits and small components of stainless steel. All are small enough to fit in a little hobby tumbler. Most .5-1" sized blocks, nuts or bolts. Some have 3/32" rods/pin coming off them. All have nooks shapes that make using a polishing wheel or dremel impossible. I am in no hurry (polishing can take all week for all I care) with the polishing, I just want it to look good without dulling my threads and spending hours of fine dremel detailing.

I assume that in a tumbler i will never get the mirror finish that one gets on a wheel. Is that true? I am ok with that. But please run me through the steps and products used to get as close as I can. The hardware and parts starts fairly deburred/sanded but sharing the process from burred to mirrored would be great.

I am seeing so many ceramic stars, ceramic triangles, powdered silica, aluminum oxide grit, corn cob meal. plastic balls ... what should i use? What should I read? what are good products? What are overly expensive products?

If I have small stainless pieces with tapped (very finely threaded) holes (3/32") in it and i want to polish the outside of the pieces but not damage the threads, do I just use a media larger than 3/32"? Or does it not matter because polishing grit in the holes will never see any forces or friction as it is in a hole? Or do I plug the hole with wax? (I can always blow material out with compressed air).

Thanks in advance for your help and ideas.

P.J. Cadmus - Fort Collins, Colorado, USA

January 31, 2013

Q. Dear All,

We have a small Stainless steel utensil making factory. We use manual buffing for our components. We tried implementing vibratory polishing through various companies in our country. We aren't able to achieve good gloss or mirror finish. Instead we have achieved very dull finish (media- plastic for deburring and ceramic, steel for polishing), Chemicals - companies use their own chemicals. We aren't able to get desired output. Can anyone give me suggestions? Components details are below for reference.

A. PJ's problem is different from JS. Size is the factor along with time. PJ could use a small vibratory mass finishing system using dry organic abrasive and polishing media. JS has volume to consider as well as finish. I am leaning to an automated buffing machine system because of the size and shape. Cost of such a system is a lot higher than mass finishing, but it would be faster. I think if you are looking for brightness rather than smooth, it can be done in a vibratory machine with dividers or a pass through system in a wet process.

AF KentonNova Finishing Systems Inc.
Hatboro, Pennsylvania

March 14, 2013

Q. We followed AF Kenton advice and we implemented the process. Still we aren't able to achieve the desired finish; moreover it is time consuming. Currently we are processing 3000 pieces per day through manual buffing, so I am searching for technology which improves my production also. Can anyone give me dipping method so that 1 hour deburring + 1 hour polishing and some time on heating method that give me desired finish.

Jagadeesan Sankaran [returning] - Chennai, Tamilnadu, India

First of two simultaneous responses -- March 18, 2013

A. Thank you for providing the volume numbers. I could have saved you some time and effort. OK. If you are not concerned with the RMS (surface finish) you can probably process this volume through a 10 cu.ft. vibratory machine using either steel or porcelain media in a wet burnishing process and a good chemical compound. After the media is broken in you should be able to improve the brightness of the product at a rate of 500/hr. The parts will look good but the finish may not be smooth but under 24RMS. If you like what you are getting now, stay with it or convert to an automated system. I can provide a couple of equipment suppliers.

AF KentonNova Finishing Systems Inc.
Hatboro, Pennsylvania

Second of two simultaneous responses -- March 19, 2013

A. Dear All,

Thank you in advance to Mr. Kenton! I'll to I will try to repay the favor!

Mr. Jagadeesan Sankaran, I think you have to search a solution with an automatic polishing machine. I would like to help, but I need more information about your product or all the products that you have to polishing.
Can we see a picture or technical drawing, of the product? I don't understand the dimensions of your product. Do you grind before polishing? How many hours per day do you work? 3000 pieces of one single type or different model?

Thank you for your information.

Alvise Carraro- Padova, ITALY

March 20, 2013

A. Yes, Jagadeesan, it might be possible to electropolish your items instead of buffing them. Please see the excellent chapter on electrolytic polishing in the "Electroplating Engineering Handbook" [link is to product info at Amazon] to understand all the implications of whether the process may be applicable to your components.
Be warned, though, that switching from buffing to electropolishing to save labor costs may introduce some new problems for you. Best of luck.

Ted Mooney, P.E. RETfinishing.comPine Beach, New Jersey

March 22, 2013

A. Sorry Ted, but the electropolishing has three big problems:

- Firstly, you cannot get mirror finishing on the metallic surface after electropolishing. If you take a SS product after this process you can't see your face reflected on it. So you cannot get the mirror finishing.
- Secondly, electropolishing is heavily polluting as a process.
- Third, the price of equipment and consumables.
I believe that we misinform, and suggest implementing automatic polishing.

Please, if you have any question I'm available!

Alvise Carraro - Padova, ITALY

March 22, 2013

Hi Alvise. Thanks for your help. It is certainly possible that automatic polishing is a better answer for Jagadeesan's situation than electropolishing or vibratory polishing. But he specifically requested: "Can anyone give me dipping method?" -- so I did.

Every technology has advantages & disadvantages relative to the others; none is "best" except it response to a detailed list of exactly what parameters are most important. For example, no dairy or pharmaceutical manufacturer will accept mechanically polished stainless steel -- electropolishing, with its freedom from nooks & crannies, is an absolute requirement there.

The best answer will always depend on the actual situation, so I find it strange when someone insists that their proposed method will be better than any possible alternate method -- while simultaneously noting they don't yet have any facts about dimensions, production rates, process sequences, work schedules etc. :-)

Thanks and regards,

Ted Mooney, P.E. RETfinishing.comPine Beach, New Jersey

March 24, 2013

Q. Dear All,

Thanks for your revert.

We finally did wet process trial with 5 mm porcelain round ball media and with good chemical compound. Process is of 90 min deburring and polishing. As a result, we are able to improve dull finish and we aren't able to get desired finish. As per report, iron content is more in our component and only up to this level, we can get the polish.

We tried implementing Electropolish also, Since is convex, we aren't able to get polish on the inner surface; moreover, iron content is more, bath has to changed very frequently and on the other hand, we are located in the city and proceeding with electropolish is very difficult.

We manufacture around 40 to 45 various types of products of various sizes and dimensions. It all depends on market needs. So while doing automation, we have to consider all the parameters. Can anyone give me more details on automation on polishing machines.

Thanks in advance.

Regards,

Jagadeesan Sankaran [returning]- Chennai, Tamilnadu, India

March 27, 2013

A. Thanks, Jagadeesan. But I think the ball is still in your court re. automatic polishing equipment. As I read the thread, Alvise is waiting to hear typical dimensions of your product, whether you grind before polishing, how many hours per day you work, and perhaps of the 3000 pieces per day, maybe how many of the size you do the most of (maybe it's impractical to automatically polish specialty items that you do only a few of).

Ted Mooney, P.E. RETfinishing.comPine Beach, New Jersey

Mirror polishing s.s sheet metal for pressure gauges

July 5, 2013

Q. Sir,
We are manufacturing s.s 304 and s.s 316 draws with some holes and some shapes in 0.8 to 1.00 mm thick sheets. Now we are doing in vibrators. Media is s.s balls dia. 3 mm. We use some buffing chemicals. We are facing problem of good finish. Sometimes we get it and sometimes not. Do you know what is the good chemical to be used good results?

Thanking you

Ravindranath Tapas - Belgaum, Karnataka, India

July 12, 2013

A. Question: In your present wet process, are you working these parts in a batch with liquid closed, or are you recirculating. Maybe a flow through system, not closed loop will work better and produce consistent results.

AF KentonNova Finishing Systems Inc.
Hatboro, Pennsylvania

August 30, 2013

A. Mr Khandelwal,
I suggest you to save time and improve the quality of s.s. parts use liquid deburring and polishing chemicals (citric acid based).

Sanjay Kumarvibratory chemical compound - Delhi,Iindia

December 8, 2013

A. DEAR,
FOR HIGH GLOSS OR MIRROR FINISH ON SS YOU WILL HAVE TO GO FOR ELECTROPOLISHING AFTER VERY GOOD DEGREASING.

M FAHEEM- LUCKNOW, U.P., INDIA

Polishing machine for Stainless steel small size cups

March 11, 2015

Q. Dear sir,
We are looking for your kind help by advising us for below.

we are small scale manufacture of stainless steel dinner cups everyday we are facing problem with our polish man that's they are not coming properly for job and often they keep quitting their job.

Because of it we could not deliver our products to our clients at the proper time and we keep losing orders from them.

So I would like to know if by vibratory machine can we polish our product.

A. Mass finishing can polish or burnish depending on what you put into the machine as a media. It was very commonly use to polish silverware at big restaurants. They call it polishing but it was actually burnishing. Media used was porcelain and the liquid chemical was important to the operation.

AF KentonNova Finishing Systems Inc.
Hatboro, Pennsylvania

March 21, 2015

Thank you for yours answer and now I am cleared about this machine. Even I have contacted the vibratory machine manufacturer and will be ordering this machine soon.

A. Ted is right. If you need a bright finish on nails, the normal method for mass finishing is to tumble what is called part on part with no media.

AF KentonNova Finishing Systems Inc.
Hatboro, Pennsylvania

April 14, 2016

Q. I am a manufacturer of silver idols. For polishing purpose I use vibratory tumbler with steel media and liquid, but yet I didn't get optimum results. Which media can I use for mirror finish? The shape of every idol is complex, so I cannot use buffing wheel. Can anyone help me with my problem?

prkash kajave - kolhapur maharstra India

June 7, 2016

Q. What's a good thing for polishing of SS? I am using centrifugal vibrating machine and SS-202 surface polishing. I need white Mirror polished surface. Than what process should I do?
Vibrator Machin ? Suggest me

A. Not sure your centrifugal system is set up to run dry organic media or not. That would be my first choice. I lieu of that a wet system using a mix of small porcelain shapes would be good; however, the chemical compound is very important. If your SS parts are machined, you may need an abrasive process first.

AF KentonNova Finishing Systems Inc.
Hatboro, Pennsylvania

June 10, 2016

adv.
It is possible to do bulk electropolishing of small ss part in our Universal electrolyte. We deliver the technological process, electrolyte composition and the device drawings. The small prototype device can be delivered too. Such stainless steel electropolishing technology (for all types of SS alloy) has been licensed to Bama Technologies from Turbigo, Italy. See the brochure called "Italian Fasteners". It is both in English and Italian.

Q. Can we do dry polishing in circular vibrator, if no then can you please let me know the reason?

Avnish Jaiswal - Mumbai, Maharashtra, India

June 23, 2016

A. Yes you can dry polish in a vibratory system; however, there are some concerns.
#1 time to process parts are long, 24 hours or more.
#2 you need to cover top of machine and seal drains
#3 You maybe able to process in less time by using treated organic media and adding a porcelain media shape to add pressure to the parts.

AF KentonNova Finishing Systems Inc.
Hatboro, Pennsylvania

July 26, 2016

Q. I am going to start up new business please suggest me machine to polish ss thank you. Basically I would deal in equestrian fittings.

Nasar Razzaqui - Kanpur, Uttar Pradesh, India

August 2, 2016

A. Any mass finishing system will work. It is more a question of your parts size and volume of parts to be processed. Bottom line, your parts have to move freely in an X,Y, and Z motion without too much contact with either the walls of the machine and other parts. See steps 1-3 previous. Media suggestions: 50#'s = 1 cu.ft. Must add new cup full every batch.

AF KentonNova Finishing Systems Inc.
Hatboro, Pennsylvania

Deburring and polishing stainless steel shackle

October 4, 2016

Q. I manufacture stainless steel D shackles in 6 mm 316 L stainless plate.
The shackles have a circular hole and a D shaped hole cut out of a 6 mm thick plate.
The length of the plate is about 45 mm and the width is about 30 mm , the circular hole is about 20 mm in diameter, the circular part of the D shaped cut out has a diameter of about 20 mm.
The 30 mm width sides of the plate have straight parallel sides, the 40 mm length has radius.
The shackles are laser cut and have sharp square edges.
I would like to de-burr the edges to radius of about 3 mm.
Please let me know if this can be achieved?

regards
Krish

krish mudalymanufacturer - Durban South Africa

October 5, 2016

A. YES! I don't think you mentioned about the surface finish requirements. Meaning to get the radius break, you need to use a rough cut ceramic media in a wet process. Time cycle is determined by hardness.

AF KentonNova Finishing Systems Inc.
Hatboro, Pennsylvania

November 18, 2016 -- this entry appended to this thread by editor in lieu of spawning a duplicative thread

Step 3) I'm currently using dry walnut shells and a polishing compound "Flitz tumbler/media additive" to achieve a mirror finish. (dry process- 8 hours). So far I have not achieved the mirror finish I'm looking for.

Any insight on processing stainless steel to a mirror finish using vibratory machines would be appreciated.

Roger

Roger Gottemployee - Toronto, Ontario, Canada

Vibratory polishing machine for stainless steel utensils

November 26, 2016 -- this entry appended to this thread by editor in lieu of spawning a duplicative thread

Q. Sir I am arun from chennai I have been holding a stainless steel utensils manufacturing company it's very difficult to get workers for hand buffing so I want to know how I can get mirror polish using vibratory finishing machine or any other suggestions. Please suggest.

A. OK It is not easy to get a polished finish on steel or SS in a short time cycle. There are a number of steps. It can take 3 to 5, depending on what you are looking for. First of all, you need to know the Ra or RMS of the surface before you start. If you you are working with processes materials, more than likely you have close to a 32 RMS. A fast cut (coarse) ceramic over a one hour period (maybe 2-4 hrs-depending on hardness) should get you down to about 22-24 RMS. The next step should be a fine cut ceramic for another hour to 4 hrs. That can bring that surface finish down to 16 - 18 RMS. Now if you are looking for brightness/reflective finish, you can go to either porcelain or steel or SS media with a burnishing compound for another for another hr or two. The end results may not be smooth but bright. If you want smooth, you may want to go to a dry process using treated organic media instead of the 3rd step wet process mentioned.
Actually you can do a 2 step dry for better results.

AF KentonNova Finishing Systems Inc.
Hatboro, Pennsylvania

December 2, 2016

At the very least, if processes like what AF Kenton suggest gets you closer to the finish you want, then your hand buffing workers will spend less time on each part.

Aluminium polishing compound

March 27, 2017

Q. Hello sir I am Adil Khan from India.
I am 22 years old; I am going to set up a separate shop for metal finishing compound for vibratory finishing machines. So sir, firstly I want manufacturer compound of aluminium metal finishing.
So sir I kindly request to you that, what is the composition of this compound?

Best way to polish tiny pieces of 304 stainless steel wire?

May 31, 2017

Q. Hi. I need to polish very small pieces of 304 stainless steel wire. They are .26" long pieces of .01" diameter wire. I want them to be as polished as possible, to look as much like a chrome plated finish as possible.

Disclaimer: It's not possible to diagnose a finishing problem or the hazards of an operation via these pages. All information presented is for general reference and does not represent a professional opinion nor the policy of an author's employer. The internet is largely anonymous & unvetted; some names may be fictitious and some recommendations may be deliberately harmful.